Room-temperature highly sensitive triethylamine detection by few-layer Nb2CTx MXene nanosheets.

MXene, a class of two-dimensional materials that are emerging as rising stars in the field of materials, are receiving much attention in sensing. Ti3C2Tx MXene, the most maturely researched MXene, is widely used in energy, biomedical, laser, and microwave shielding applications and has also been expanded to gas sensing and wearable electronics applications. Compared with Ti3C2Tx, Nb2CTx MXene is more difficult to etch and has higher resistances at room temperature; so, few studies have been reported on their use in the sensing field. Based on the preparation of few-layer Nb2CTx MXene by intercalation, this study thoroughly examined their gas-sensing properties. The successfully prepared few-layer Nb2CTx showed good selectivity and high sensitivity to triethylamine at room temperature, with response values up to 47.2% for 50-ppm triethylamine and short response/recovery time (22/20 s). This study opens an important path for the design of novel Nb-based MXene sensors for triethylamine gas detection.